We totally get the Fourth Amendment crusade against testing the DNA of any and every person arrested on felony charges:

It's invasive, preemptive and Big Brother-esque.

But even if only 50 percent of said arrestees are convicted of their charges — a 2009 figure cited by Brown-appointed Presiding Justice J. Anthony Kline before declaring the tests unconstitutional last week in state appellate court — a close-to-home accused serial killer makes us wonder. Might a couple big fish be worth the discomfort/righteousness of the exonerated?

Including one of the biggest, baddest fish ever to (allegedly) rape and pillage Los Angeles:

Lonnie Franklin Jr., suspected of killing at least 10 black prostitutes in South L.A. And just yesterday, though Franklin's has pleaded “not guilty” to all charges so far, LAPD investigators announced they've linked 230 more missing persons to the horrific spree.

Lonnie Franklin Jr.

Lonnie Franklin Jr.

In August 2008, before Franklin was arrested, Christine Pelisek, former LA Weekly crimehunter, named the ruthless, faceless serial killer “The Grim Sleeper” after stumbling across a back room filled with victim photos and clues at the LAPD's homicide headquarters.

Today, the Wall Street Journal points to serial killers Dennis Rader and Gary Leon Ridgwayne, both caught on pre-conviction DNA tests, as prime living arguments to counter the personal-privacy diehards.

But Franklin's capture might make an even stronger case:

The science of testing for familial DNA was hotly pursued by LAPD in 2008 when police realized that the Grim Sleeper sociopath, who had been slaughtering people since 1985, had kept his nose clean and stayed out of jail. …

No doubt, working with police every day as an LAPD mechanic, he knew every trick for avoiding arrest. He knew cop lingo and police habits.

But then, his son screwed up and apparently got nabbed by cops. His son got a mouth swab. His son's DNA test lit up like a Christmas tree:

His son's DNA, police tell LA Weekly, matched in so many ways that LAPD knew they'd found a close relative of Grim Sleeper, the most elusive serial killer to ever haunt the Western United States.

Felony trials are long and hard to prove. For guys as system-savvy as Franklin, avoiding jail time is only a matter of delays and precautions and slippery legal tactics. Swabbing for DNA at the time of arrest could provide access to the smartest — and therefore, perhaps, most dangerous — of criminals.

The (very legitimate) fear at the heart of the ACLU fight against arrestee DNA testing is that the entire sample is kept in an FBI database, instead of just used by local police for identification, like a familial fingerprint.

We're the first to raise an eyebrow at anything that plays into the feds' roundabout drive to obtain full biometric profiles of everyone who so much as talks to police. See: “FBI Documents Reveal ICE's 'Secure Communities' Program Was Mandated to Further FBI's Own Creepy Biometric Database.”

From a Journal print story: “Some fear that gene technologies will be developed down the road to unearth even more private information, like whether someone has a predilection for violence.”

Indeed: That would suck. Why don't scientists just identify the serial-killer gene already, so we can quarantine these Franklin types before they raise the first blade, “Minority Report” style?

[@simone_electra/swilson@laweekly.com]

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