Ink AnalysisA Weapon Against Crime by ... - ACS Publications

14 Ink Analysis—A Weapon Against Crime by

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Detection of Fraud RICHARD L. BRUNELLE and A. A. CANTU B u r e a u of A l c o h o l , T o b a c c o , and F i r e a r m s , U. S. Treasury D e p a r t m e n t , W a s h i n g t o n , D . C . 20026

For decades, document examiners have searched f o r ways to detect fraudulent documents other than by t r a d i t i o n a l methods such as handwriting a n a l y s i s , t y p e w r i t i n g i d e n t i f i c a t i o n , o b l i t -erated and indented w r i t i n g , deciphering and determination of the sequence of w r i t i n g s . New methods f o r d e t e c t i n g fraudulent documents developed slowly f o r s e v e r a l reasons: (a) a n a l y s i s of ink and paper causes s l i g h t d e s t r u c t i o n to the document; (b) document examiners considered the p r e s e r v a t i o n of the o r i g i n a l c o n d i t i o n of the documents very important; and (c) document examiners with few exceptions were t r a i n e d i n the areas of hand- w r i t i n g and t y p e w r i t i n g a n a l y s i s but lacked the scientific t r a i n i n g to explore chemical and p h y s i c a l methods f o r use i n d e t e c t i n g fraudulent documents. The need f o r new and b e t t e r methods to detect fraud has continuously been expressed by various agencies p r i m a r i l y w i t h i n the Treasury Department and the C r i m i n a l Tax D i v i s i o n of the J u s t i c e Department. For example, agents of the I n t e l l i g e n c e D i v i s i o n of the I n t e r n a l Revenue Service need to know not only who signed a p a r t i c u l a r document, but when the document was pre-pared or signed. It i s not uncommon f o r a dishonest taxpayer to backdate a r e c e i p t or s e r i e s of records to s u b s t a n t i a t e a tax c l a i m on h i s income tax r e t u r n . Often documents are created or a l t e r e d a f t e r an i n v e s t i g a t i o n begins i n an attempt to account f o r taxable income, which i n some cases involves s i z a b l e sums. Firearms records are o f t e n created or a l t e r e d a f t e r the s t a r t of an i n v e s t i g a t i o n of a suspected firearms dealer. Since c e r t a i n types of weapons such as machine guns, grenades, sawed- o f f shotguns and others must be r e g i s t e r e d with the Bureau of A l c o h o l , Tobacco and Firearms (ATF), proof of t h e i r l e g a l r e g i s - t r a t i o n must be presented. The J u s t i c e Department has an urgent need to detect fraud i n many organized crime cases because it is o f t e n very difficult to a s s o c i a t e a suspect with the p a r t i c u l a r offense except by the

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d e t e c t i o n of fraud through document a n a l y s i s . The S e c u r i t i e s and Exchange Commission (SEC) i s f r e q u e n t l y concerned with fraud i n the i l l e g a l manipulation of the stock market. Many of t h e i r cases i n v o l v e the a n a l y s i s of hundreds of documents which may t y p i c a l l y show the c r e a t i o n and d i s s o l u t i o n of companies and the sale of u n r e g i s t e r e d stock f o r the f i n a n c i a l g a i n of a few greedy people at the expense of the unknowing stockholders. It i s obvious that thousands of spurious documents are passed d a i l y to government and other agencies and, a f t e r t r a d i t i o n a l methods f a i l to detect f r a u d , only the a p p l i c a t i o n of chemical and p h y s i c a l methods of a n a l y s i s remain. Both the ink and paper of a document possess p o t e n t i a l value i n d e t e c t i n g p o s s i b l e fraud through the use of s c i e n t i f i c techniques. Within the Bureau of ATF, the I d e n t i f i c a t i o n Branch of the Laboratory met the challenge placed on i t s chemists by the p r e s s i n g needs of the many enforcement groups f o r t h i s s c i e n t i f i c type of work. These chemists discovered that the a p p l i c a t i o n of w e l l e s t a b l i s h e d and proven s c i e n t i f i c methods of ink a n a l y s i s (JL) i n conjunction with a w e l l maintained up-todate standard ink l i b r a r y could lead to the i d e n t i f i c a t i o n and dating of w r i t i n g inks ( 2 ) . This accomplishment has proven to be extremely v a l u a b l e whenever the date of p r e p a r a t i o n of a document i s questioned. Paper a n a l y s i s , which can provide v a l u able information i n these e f f o r t s ( 3 ) , w i l l not be dealt with i n this a r t i c l e . The value of the systematic approach to ink i d e n t i f i c a t i o n and dating used by the Bureau of ATF group i s evidenced by the many requests f o r the s e r v i c e s of the Laboratory. Over the past s i x years s e v e r a l hundred document cases have been processed and the technique has been accepted by the c o u r t s . Furthermore, t h i s work has to the present detected s e v e r a l m i l l i o n d o l l a r s i n tax evasion. Systematic Approach to Ink

Identification

P r i o r to the research c a r r i e d out by the Bureau of ATF I d e n t i f i c a t i o n Branch the s p e c i f i c i d e n t i f i c a t i o n and dating of w r i t i n g inks had not been accomplished. Ink dating was l i m i t e d to the determination of periods of time when gross changes were made i n t h e i r compositions. For example, the change from o i l base solvents to g l y c o l bases provided a date ( c i r c a 1952) p r i o r to which g l y c o l b a l l p o i n t inks d i d not e x i s t . In the new and r a t h e r unique approach to t h i s problem, the i d e n t i f i c a t i o n of inks on questioned documents depends on the maintenance of an up-to-date standard ink l i b r a r y . The a c t u a l i d e n t i f i c a t i o n i s made by comparing the c h a r a c t e r i s t i c s , or points of i d e n t i f i c a t i o n , r e s u l t i n g from the a n a l y s i s of the questioned ink with the corresponding r e s u l t s obtained from d r i e d samples (on standard paper) of the known standard inks i n the l i b r a r y . Clearly, the l a r g e r the number of c h a r a c t e r i s t i c s



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that match, the higher the degree of r e l i a b i l i t y of the i d e n t i f i cation. The methods of a n a l y s i s used to compare the inks are w e l l e s t a b l i s h e d laboratory techniques which have general acceptance i n the s c i e n t i f i c community. The i n i t i a l method f o r comparing the questioned and known specimens i s by performing non-destruct i v e and somewhat simple but important t e s t s to determine the c o l o r , type ( b a l l p o i n t , f i b e r t i p , r o l l i n g marker, f o u n t a i n pen, e t c . ) , and i n f r a r e d luminescence p r o p e r t i e s . But most e s s e n t i a l are the chemical c h a r a c t e r i s t i c s which r e q u i r e the removal of micro-samples from the questioned ink w r i t i n g . With such samples one can perform t h i n l a y e r chromatography (TLC). This technique makes p o s s i b l e the separation of both n o n - v o l a t i l e c o l o r e d and non-colored compounds used i n the ink f o r m u l a t i o n . A paper sample or c o n t r o l i s u s u a l l y examined simultaneously. The ink chromatograms shown i n Figures 1-5 show d i f f e r e n c e s between s i m i l a r c o l o r e d inks of v a r i o u s types when analyzed by TLC. The d i f ferences are obvious from o b s e r v a t i o n of the separated c o l o r e d components. Since the dyes and pigments i n the w r i t i n g inks are c o l o r e d and the s e p a r a t i o n of the dye components can be seen v i s u a l l y , t h i s phase of the i d e n t i f i c a t i o n process of a questioned i n k can be u t i l i z e d to r a p i d l y scan through the standard l i b r a r y to search f o r inks which may have s i m i l a r TLC chromatograms . In a c t u a l p r a c t i c e , t h i s procedure permits narrowing the search to a l l but p o s s i b l y a few i n k s . These inks w i t h somewhat s i m i l a r chromatograms are f u r t h e r examined by observing f l u o r e s cent components on the TLC p l a t e using u l t r a v i o l e t l i g h t . I f t h i s l e v e l of examination and comparison does not show uniqueness and i f s u f f i c i e n t questioned ink i s a v a i l a b l e , other examinations can be performed. These examinations include the use of d i f f e r ent TLC media ( p l a t e s ) and d i f f e r e n t solvent systems. To o b t a i n f u r t h e r c h a r a c t e r i z i n g features w i t h any of the TLC plates, r e l a t i v e amounts of the v a r i o u s dyes present i n the f o r m u l a t i o n are determined using spectrophotometry. These examinations u s u a l l y narrow the p o s s i b i l i t i e s to only one standard ink i n the l i b r a r y . When we reach the point where these examinations cannot d i s t i n g u i s h between the questioned and standard ink i t i s then poss i b l e to conclude w i t h a high degree of s c i e n t i f i c c e r t a i n t y that the questioned ink matches i n every respect a s p e c i f i c ink formul a t i o n i n the l i b r a r y . To f u r t h e r conclude that two inks come from the same f o r m u l a t i o n i s based on the f a c t t h a t , of about 3,000 w r i t i n g inks i n the standard i n k l i b r a r y , a l l inks produced by d i f f e r e n t manufacturers have been found to be d i s t i n g u i s h a b l e when the d i f f e r e n c e i s i n the n o n - v o l a t i l e components. Once the questioned ink has been i d e n t i f i e d , i . e . , matched w i t h a standard ink, the f i r s t production date of the standard ink can be determined from i n f o r m a t i o n s u p p l i e d by the manufacturer. I n q u i r i e s c a r r i e d out by the Bureau of ATF I d e n t i f i c a t i o n Branch have shown that the v a r i o u s i n k formulations change f r e quently, and every time a formula changes a date i s provided



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p r i o r to which that ink was not i n existence. As a r e s u l t i t i s p o s s i b l e on many occasions to determine that a questioned ink used to prepare a document matched a standard ink which was not i n existence on the date the document was a l l e g e d l y prepared. Obviously, the e f f e c t i v e n e s s of the dating technique r e l i e s on frequent formulation changes and on the degree of i d e n t i f i c a t i o n . It should be mentioned that i n some cases i t may happen that a questioned ink can be more p o s i t i v e l y i d e n t i f i e d through presence of f l u o r e s c e n t or other unique components i n the formul a t i o n . When s u f f i c i e n t questioned ink i s a v a i l a b l e and the p r o p r i e t o r y formula composition has been f u r n i s h e d , f u r t h e r a n a l y s i s can lead to the i d e n t i f i c a t i o n of a component which may provide a d d i t i o n a l proof of the i d e n t i t y of the ink. For example, there are a v a r i e t y of f a t t y a c i d s , r e s i n s , and v i s c o s i t y adjusters added to inks which can be r e a d i l y i d e n t i f i e d by TLC or gas l i q u i d chromatography (GLC), when s u f f i c i e n t ink i s a v a i l a b l e . As f u r t h e r examples, amorphous carbon and g r a p h i t e , which are common d i s p e r s i o n i n g r e d i e n t s i n b a l l p o i n t i n k s , can be d i s t i n g u i s h e d using e l e c t r o n d i f f r a c t i o n methods. The l a r g e r number of points of i d e n t i f i c a t i o n that are determined, the more c e r t a i n becomes the c o n c l u s i o n regarding the i d e n t i f i c a t i o n of questioned i n k s . Such f o r e n s i c s c i e n t i f i c philosophy i s true not only of ink comparison but of other types of p h y s i c a l evidence such as s o i l , p a i n t , h a i r , b u l l e t s and f i n gerprints . The Bureau of ATF Ink L i b r a r y of standard ink samples i s e s s e n t i a l l y complete w i t h respect to a l l domestic and most European-produced inks f o r the past few decades. However, the l i b r a r y does not c o n t a i n a l l of the inks produced i n the world nor w i l l t h i s ever be p o s s i b l e . This does not detract from the p r a c t i c a b i l i t y of the ink i d e n t i f i c a t i o n technique despite the rare occurrence of a n o n - i d e n t i f i c a t i o n . However, since i n a c t u a l p r a c t i c e i t i s not p o s s i b l e to o b t a i n a l l of the inks i n the world, the comparison i s based on the p r o b a b i l i t y or degree of c e r t a i n t y that a questioned ink matches an e x i s t i n g standard ink. The n o n - i d e n t i f i c a t i o n of questioned inks can occur when the corresponding standard ink was not s u p p l i e d , or when the questioned ink c h a r a c t e r i s t i c s changed s u f f i c i e n t l y due to d e t e r i o r a t i n g c o n d i t i o n s such as photochemical degradation caused by extreme exposure to l i g h t . A p p l i c a t i o n to Actual Cases This systematic approach to ink i d e n t i f i c a t i o n and ink dating as stated e a r l i e r has been a p p l i e d to s e v e r a l hundred cases over the past s i x years. In a large percentage of cases examined, i t was p o s s i b l e to show that documents were backdated because the w r i t i n g ink used was not i n existence at the time the document was a l l e g e d l y w r i t t e n .



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The courts have h e l d that s c i e n t i f i c methods of a n a l y s i s are acceptable i n the courts i f the techniques used have general acceptance i n the s c i e n t i f i c community (Frye v. U.S.) ( 4 ) . The ink i d e n t i f i c a t i o n technique s a t i s f i e s these c r i t e r i a because a l l of the methods used to analyze inks are w e l l e s t a b l i s h e d and proven a n a l y t i c a l t o o l s and t h i s p o i n t has been conceded by experts f o r the defense i n s e v e r a l cases. Usually the ink testimony i s o f f e r e d as c o r r o b o r a t i v e e v i dence i n a case and o c c a s i o n a l l y i t has been used as primary evidence such as i n S t o l l e r v. U.S. (5) t r i e d i n Miami, F l o r i d a . In t h i s case, testimony based on the ink dating technique was presented f o r the f i r s t time. Several inks were i d e n t i f i e d i n t r a v e l and expense d i a r i e s f o r the years 1965, 1966, and 1967. The a n a l y s i s revealed that a large number of the inks used i n the d i a r i e s were not a v a i l a b l e commercially u n t i l a f t e r the years i n question, i n d i c a t i n g the e n t r i e s were backdated. The testimony was used as a r e b u t t a l to impeach the testimony of the defendant and placed c o n s i d e r a b l e doubt on the a u t h e n t i c i t y of the d i a r i e s . Thousands of d o l l a r s of taxable income were i n volved and the defendant became l i a b l e f o r the tax assessed by the I n t e r n a l Revenue S e r v i c e . In U.S. v. Wolf son (6), t r i e d i n the Southern D i s t r i c t of New York, the defendant charged the government with using a spurious document to prosecute him f o r v i o l a t i o n of SEC r e g u l a t i o n s i n v o l v i n g the C a p i t a l T r a n s i t System. He claimed that one of a seven page document was a l t e r e d and was not the o r i g i n a l i n s t r u ment . A n a l y s i s revealed that ink prepared from the same formulat i o n was used on each of the seven pages. This t e s t , together with the f i n d i n g s from paper a n a l y s i s and watermark examination conducted on the documents, helped to s u b s t a n t i a t e the a u t h e n t i c i t y of the questioned document. The i n k testimony was accepted by the court as v a l i d and persuasive and the examinations conducted by the Bureau of ATF I d e n t i f i c a t i o n Branch were h e l d i n the balance by the court even though a large sum was spent on defense expert work and testimony. In another case, an o f f i c i a l of a large New York bank was accused of i l l e g a l l y awarding loans to small business concerns. In t h i s case, U.S. v. Meyers ( 7 ) , t r i e d i n the Southern D i s t r i c t Court of New York, ink and handwriting analyses a s s i s t e d i n showing that many of the loan a p p l i c a t i o n forms were prepared by the bank o f f i c i a l r a t h e r than the loan a p p l i c a n t . The s c i e n t i f i c testimony presented f o r the government was accepted by the court and was not challenged by the defense. In Memphis, Tennessee, the defendant was charged with perj u r y r e s u l t i n g from testimony given at the defendant's f e d e r a l income tax evasion t r i a l . In U.S. v. Sloan ( 8 ) a c o n v i c t i o n was obtained and during the t r i a l c e r t a i n documents were o f f e r e d as evidence. I t was because of these instruments that p e r j u r y charges were made.



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The defendant claimed he was i n v e s t i n g money f o r an anonymous r i c h c l i e n t through land purchases which were supposed to have been made from 1958 through 1966. Over a h a l f a m i l l i o n d o l l a r s of taxable income was i n v o l v e d . The government claimed the defendant was i n v e s t i n g h i s own money and was using the r i c h c l i e n t scheme to avoid paying the tax. To prove h i s case, Sloan introduced a four page agreement dated 1958, s t a t i n g that the defendant was to i n v e s t sums of money f o r an anonymous c l i e n t covering an i n d e f i n i t e p e r i o d of time. Also introduced were a s e r i e s of notes dating from 1958 to 1966 which presumably was the proof of these investments. Ink a n a l y s i s of the w r i t i n g on each page of the agreement and the notes, showed that the same ink formulation was used on the documents. Figure 6 shows the s i m i l a r i t y among these chromatograms . In a d d i t i o n , the f i n d i n g s revealed that the documents could not have been i n existence i n 1958, because a unique dye i d e n t i f i e d i n the ink was f i r s t synthesized by Ciba Chemical Corp. i n 1959 and the ink formulation was not produced u n t i l 1960. The testimony i n v o l v i n g the i n k a n a l y s i s was primary e v i dence and i t s use was s u f f i c i e n t to o b t a i n a c o n v i c t i o n of perj u r y even though three experts were employed by the defense to counter the ATF ink testimony. The defendants i n the case, U.S. v. Colasurdo ( 9 ) , t r i e d i n the Southern D i s t r i c t of New York, were a l l e g e d l y connected with organized crime operations and were charged with the formation and d i s s o l u t i o n of companies to achieve personal f i n a n c i a l g a i n at the expense of the s t o c k h o l d e r s . A f t e r almost two months of t r i a l , testimony based on ink i d e n t i f i c a t i o n and i n k d a t i n g was introduced by Bureau of ATF chemists. The f i n d i n g s , which were accepted by the court over o b j e c t i o n of defense counsel, revealed that a document dated 1965 o f f e r e d as evidence by the defense was backdated. The b a l l point i n k used to prepare the signature on t h i s instrument was not produced u n t i l 1968. Although the defense secured the s e r v i c e s of experts to counter the ATF ink testimony, the evidence was accepted by the courts. The defense appealed the g u i l t y v e r d i c t p a r t l y on the b a s i s of the ink testimony, but the U.S. Court of Appeals f o r the Second C i r c u i t a f f i r m e d the c o n v i c t i o n . Later the U.S. Supreme Court denied c e r t i o r a r i . P r i o r to the appeal of the Colasurdo d e c i s i o n , ink testimony was o f f e r e d i n the U.S. v. Bruno (10), t r i e d i n P h i l a d e l p h i a , Pennsylvania. The request f o r l a b o r a t o r y a s s i s t a n c e was i n i t i ated by the C r i m i n a l Tax D i v i s i o n of the J u s t i c e Department. The charge i n v o l v e d the evasion of income tax from the s a l e o f c e r t a i n vending machines and the premises on which the equipment was l o c a t e d .



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A n a l y s i s revealed that ink used to prepare a signature on a document dated 1965 was not a v a i l a b l e commercially u n t i l 1967. A combination of i n g r e d i e n t s that was unique to one ink manufact u r e r i n a l l of the U.S. and i n Europe was i d e n t i f i e d . In t h i s case, the p r e s i d i n g judge a f t e r two weeks of t r i a l , r u l e d that the evidence was not c o n c l u s i v e because the ATF Laboratory d i d not have access to a l l f o r e i g n i n k s . In a d d i t i o n , the ink testimony was the primary evidence and i n the judge's o p i n i o n the s t a t e of the a r t of ink i d e n t i f i c a t i o n had not reached a reasonable degree of s c i e n t i f i c c e r t a i n t y . This r u l i n g was made d e s p i t e f i v e p r i o r r u l i n g s by d i f f e r e n t courts i n d i f f e r e n t j u r i s d i c t i o n s upholding the ink i d e n t i f i c a t i o n technique as v a l i d and persuasive. The U.S. Court of Appeals f o r the 2nd C i r c u i t a f f i r m e d the c o n v i c t i o n of Colasurdo a f t e r c o n s i d e r i n g an appeal based on reasoning that the ink i d e n t i f i c a t i o n technique was not yet proven. In t h e i r o p i n i o n , the Court considered the r u l i n g made by the Judge i n the Bruno Case, but were not p a r t i c u l a r l y i n f l u enced by h i s f a i l u r e to accept the ink i d e n t i f i c a t i o n technique. The most recent d e c i s i o n regarding the a c c e p t a b i l i t y of the i n k method was the d e n i a l of the U.S. Supreme Court to review the Colasurdo Case. Since then ink a n a l y s i s testimony has been accepted i n at l e a s t eight cases. In summary, i t appears from the r u l i n g s made by the v a r i o u s courts that the ink i d e n t i f i c a t i o n and ink d a t i n g technique are g e n e r a l l y acceptable f o r court purposes. Future Developments i n Ink I d e n t i f i c a t i o n Work Absolute i d e n t i f i c a t i o n of w r i t i n g inks i s d i f f i c u l t because a l l of the components which were o r i g i n a l l y put i n t o the ink by the manufacturer cannot be determined on a sample taken from a questioned document. P o s i t i v e i d e n t i f i c a t i o n i s only poss i b l e when i t can be e s t a b l i s h e d that a unique dye or combinat i o n of i n g r e d i e n t s was used i n the f o r m u l a t i o n . The success of the present ink i d e n t i f i c a t i o n program depends l a r g e l y on the cooperation of the v a r i o u s ink manufact u r e r s who supply the known i n k s . Without t h e i r h e l p , s u f f i c i e n t standard samples would not be a v a i l a b l e to compare with quest i o n e d inks f o r the approach to be p r a c t i c a l . The Bureau of ATF I d e n t i f i c a t i o n Branch has been very f o r t u n a t e because ink companies have recognized the value of t h i s type of program to the law-abiding c i t i z e n s . They have been extremely cooperative i n supplying us w i t h ink specimens and w i t h experts i n ink technology to present testimony i n court whenever necessary. Since the e f f e c t i v e n e s s o f the i n k d a t i n g program depends on frequent formula changes, the Bureau of ATF I d e n t i f i c a t i o n Branch i s c u r r e n t l y i n v e s t i g a t i n g the f e a s i b i l i t y of a more absolute i d e n t i f i c a t i o n system that can be used by a l l i n k manufacturers. I t has been proposed that each producer add markers



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or tags to make p o s s i b l e a p o s i t i v e i d e n t i f i c a t i o n of t h e i r product. This approach w i l l allow the determination of the year the ink was produced i f the markers are changed y e a r l y . This w i l l s e t t l e at l e a s t two current problems f a c i n g the e f f e c t i v e ness of the method: (a) Recently an i n c r e a s i n g number of ink manufacturers have not changed t h e i r formulations, p a r t i c u l a r l y t h e i r n o n - v o l a t i l e components. (b) N o n - i d e n t i f i c a t i o n sometimes occurs due to severe aging c o n d i t i o n s of a questioned ink. Ink manufacturers can a l s o b e n e f i t from ink tagging to s e t t l e customer disputes concerning the age of i n k s . The value and a p p l i c a t i o n s of the Bureau of ATF Ink I d e n t i f i c a t i o n and Dating Program to law enforcement problems i s now w e l l recognized i n t e r n a t i o n a l l y . The I n t e r n a t i o n a l A s s o c i a t i o n of I d e n t i f i c a t i o n , one of the world's l a r g e s t p r o f e s s i o n a l organi z a t i o n s i n f o r e n s i c science, presented the h i g h l y coveted Dondero Award to a Bureau of ATF chemist f o r the outstanding cont r i b u t i o n to the f i e l d of ink i d e n t i f i c a t i o n . This laboratory, however, must continue to improve the e f f e c t i v e n e s s of i t s ink i d e n t i f i c a t i o n and dating program through the development and implementation of a s u i t a b l e marking or tagging system.

Literature Cited 1.

T h o l l , J., POLICE (1960) pp7-15. See a l s o references appearing on p u b l i c a t i o n 2 below. 2. B r u n e l l e , R. L. and Pro, M. J . , J . ASSOC. OFFIC. ANAL. CHEM. (1972) 55, pp 823-826. 3. B r u n e l l e , R. L., Washington, W. D., Hoffman, C. M. and Pro, M. J . , J . ASSOC. OFFIC. ANAL. CHEM. (1971) 54, pp 920-924. 4. Frye v. U.S. 293 F. 1013 (D.C. C i r 1923). 5. S t a l l e r v. U.S., Miami, F l a . (1969). 6. U.S. v. Wolfson, N.Y., N.Y. (1970). 7. U.S. v. Meyer, N.Y., N.Y., (1970). 8. U.S. v. Sloan, Memphis, Tenn. (1970). 9. U.S. v. Colasurdo, New York C i t y 1970 (Second C i r c u i t of Appeals, Docket Nos. 71-1373-4-5-6, Dec. 6, 1971). 10. U.S. v. Bruno, Phil., Pa. (1971).


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