The series 4 finale of Sherlock cleverly illustrates the dangers of allowing the inmates to run the asylum. The show regularly covers behaviors that would alarm any employer, such as Sherlock abusing drugs, firing guns indoors whenever frustrated, and generally being delightfully bizarre. These oddities are some of the many reasons that Sherlock is a consultant for, rather than an employee of, the local authorities.

They also explain why Sherlock has no regular employees to speak of, unless you count his secret network of informants. This series introduces Sherlock’s sister, who is comprised of equal parts evil and intellect. When she takes over the high security facility where she has been housed for decades for being “too clever,” all bets are off.

The fact that the facility’s employees ignore established policies and protocols for handling this particular inmate has devastating consequences. The facility certainly could have used some advice on employee screening, training, and discipline for failure to follow procedures. It also may have wanted to invest in some serious psychological testing of any employees, though screening applicants by use of psychological tests may raise ADA concerns if the tests are used to detect mental impairments.

Such screenings may also implicate rights under state law or raise discrimination issues, depending on the types of questions asked in the test. If lawful, a psychological test should be given only after an offer of employment has been extended, because a pre-offer psychological examination may constitute a prohibited pre-offer medical examination under the ADA. Regardless, I doubt any psychological screening could have prepared the facility to handle Sherlock’s little sister.

Some general takeaways for employers are:

1. Using sword-wielding clowns and bleeding portraits to frighten an individual into telling the truth is very effective, but still not acceptable behavior.

2. Double-check that any glass walls in your facility actually have glass in them.

3. Do not leave employees alone with highly dangerous geniuses with a particular talent for mind control.

4. Beware of inmates–or employees–converting areas of the facility for their own personal uses.

5. Finally, even the most seemingly complex problems can sometimes be solved with a little love.