Trying to Lerp Multiple lights

I was following the stealth tutorial from unity and I tried adding a lerp to all the camera lights when the alarm goes off, but I get the error

Assets/Scripts/CCTVPlayerDetection.cs(64,88): error CS0165: Use of unassigned local variable newIntensity’
`

What Am I doing wrong?

using UnityEngine;
using System.Collections;

public class CCTVPlayerDetection : MonoBehaviour 
{
	private GameObject player;
	private LastPlayerSighting lastPlayerSighting;
	private Light [] spotLights;
	private float lightHighIntensity = 7f;
	public float lightLowIntensity = 4f;


	void Awake()
	{
		player = GameObject.FindGameObjectWithTag(Tags.player); 
		lastPlayerSighting = GameObject.FindGameObjectWithTag(Tags.gameController).GetComponent<LastPlayerSighting>();
		GameObject[] CameraGameObjects = GameObject.FindGameObjectsWithTag(Tags.spotLight);

		spotLights = new Light[CameraGameObjects.Length];

		for( int i=0; i < spotLights.Length; i++)
		{
			spotLights _= CameraGameObjects*.light;*_ 

* }*
* }*

* void Update()*
* {*
* IntruderDetect ();*
* }*

* void OnTriggerStay(Collider other)*
* {*
* if(other.gameObject == player)*
* Vector3 relPlayerPos = player.transform.position - transform.position;*
* RaycastHit hit;*

* if(Physics.Raycast (transform.position,relPlayerPos,out hit))*
* {*
* if(hit.collider.gameObject == player)*
* {*
* lastPlayerSighting.position = player.transform.position;*
* }*
* }*
* }*
* }*

* void IntruderDetect()*
* {*
* float newIntensity;*

* for(int i = 0; i < spotLights.Length; i++)*
* {*
* if(lastPlayerSighting.position != lastPlayerSighting.resetPosition)*
* {*
* newIntensity = lightHighIntensity;*
* }*
* else if(lastPlayerSighting.position == lastPlayerSighting.resetPosition)*
* {*
* newIntensity = lightLowIntensity;*
* }*
spotLights.intensity = Mathf.Lerp (spotLights_.intensity, newIntensity, lastPlayerSighting.fadeSpeed * Time.deltaTime);
* }
}*_

}

set newIntensity to a default value at the beginning, before any "if"s or “elses”.
frustratingly unity/c# treats a variable that’s only set when it’s nested in an “if” statement as undefined for error tracking even if an “if/else” makes setting the variable inevitable.

[edit] actually in this case your value could get through as null, but even if you fixed that the above would be true.
you need a value to get through even if both conditions are false.