(1) From G. Malcolm Laws, Jr., Native American Balladry, rev. ed (1964, pp. 250-151):

I 9
BRADY
(Duncan and Brady)
Duncan kills Brady the policeman because he has wrecked Duncan's combination grocery and barroom. Mrs. Brady takes the news calmly and remarks to the children, "Well, all draw a pension when your daddy die".

Duncan, Duncan was a-tendin' bar
When in walked Brady with a shinin' star;
Cried, "Duncan, Duncan, you are under arrest!"
And Duncan shot a hole in Brady's breast.

Lomax, Our Singing Country, 333, lO, m. (a composite text, with tune from L.C. Record 1865. "Duncan and Brady"). Brown II, 571, 2 and chor. (N.C.); notes and refs. Gordon, 45, 2 sts. Gordon, Adventure, July lO, 1923, frag. of 5 sts. Odum and Johnson, The Negro and His Songs, 208, frag. of 4 sts. Sandburg, 198, frag. of 1d, m. (Neb. via Mo.); 4 sts. and 2 refrains, from R. W. Gordon's collection. Scarborough, 85, fragnents and 7 sts.
(Tex.). L.C. Records 1787 A2 (N.Y. Sung by B.L. Lunsford); 3978 B3 (Tex.); 1329 A2 & B2 (Ala.)

(2) Meade et al., Country Music Sources (2002, p. 67):

120. DUNCAN AND BRADY LAWS I9
[Ref: (3) Laws (1964), pp. 250-1; (5) 'Brady and Duncan,' Henry Truvillion, July 11, 1933, LC CYL-16-1O, 'Brady, Brady,' sung by negro convicts at the State Penitentiary, Parchman, Miss, 9-1O, August, 1933, LC 1865-A-1, 'Brady,' Bascom Lamar Lunsford, February, 1935, LC 1787-A-2, 'Brady,' Blind Jesse Harris, July 24, 1937, LC 1329-B-2, 'Brady and Duncan,' Will Starks, 1942, LC AFS-6652-Bl.]

Been On The Job Too Long (GEX 2456-) - Wilmer Watts & His Lonely Eagles (vcl w/gtr & bjo) - 10/29/1929 NYC.
Pmt 321O [1686] NWR 245
Bwy 8248 [1686] Yaz 2028(cd)

(3) From The Traditional Ballad Index:

Duncan and Brady [Laws I9]
DESCRIPTION: Policeman Brady walks into Duncan's bar and attempts to arrest the latter. Duncan, unwilling to have his business ruined, shoots Brady. Neither Brady's family nor those around Duncan seem to care much; Brady's wife looks forward to getting his pension
AUTHOR: unknown
EARLIEST DATE: 1930 (recording, Wilmer Watts & the Lonely Eagles)
KEYWORDS: murder family
FOUND IN: US(MW,SE)
REFERENCES (4 citations):
Laws I9, "Brady (Duncan and Brady)"
Sandburg, pp. 198-199, "Brady" (2 texts, 1 tune)
Botkin-MRFolklr, p. 596, "Duncan and Brady" (1 text, 1 tune)
DT 660, DUNCBRAD
RECORDINGS:
Wilmer Watts & the Lonely Eagles, "Been on the Job Too Long" (Paramount 3210, 1930; on TimesAint01)
CROSS-REFERENCES:
cf. "Casey Jones (I)" [Laws G1] (lyrics)
File: LI09

~Masato